Marianne Pinhoe is a member of the Pinhoe family and Joseph Pinhoe's sister. She lives in Ulverscote (as do the other Pinhoes) and has magical abilities. As she has a lot of dwimmer, she was to be the next Gammer of the Pinhoe family (which she did not want). Christopher Chant had her sent to Chrestomanci Castle in order to study dwimmer after he had the Farleigh family magic removed.